There are three major methods of attaching a fabric, plastic or leather seat trim cover to an automotive vehicle seat resilient body typically made from an expanded polymeric foam. The first method is to embed wires within the resilient body. A C-shaped metal piece is wrapped around the wire embedded in the foam and is also threaded into the opening between a cord sewn on the inside of the cover. A closure device compresses the C-shaped connector, closing it, thereby entrapping the cord with the embedded wire and fastening the trim cover to the resilient body. This technique is often referred to as the hog ring method.
A second major technique is to utilize a hook and loop type fastener attachment where embedded strips of hooks will engage with a series of loops. Typically, the hooks will be embedded within the foam, and a series of strips of loops will be sewn to the inside trim cover.
A third major method of attaching a seat cover to the trim is the utilization of adhesive.